Immunization
Immunization is a way of preventing a person from getting a disease. This is done by making the person's body come into contact with a bit of the disease so that the body learns how to fight it. The body's ability to fight off a disease is called its immune system.
The material is known as an immunogen. Immunization is the same as inoculation and vaccination because inoculation and vaccination use an infecting agent (something that infects) in the same way that immunization does.
When the human immune system is exposed to an infection once, it can learn how to cope quickly if it is exposed to it again. By exposing an individual to an immunogen in a controlled way, the body will be able to protect itself from that infection later on in life.
Immunization Media
Dr. Schreiber of San Augustine giving a typhoid inoculation at a rural school, San Augustine County, Texas. Transfer from U.S. Office of War Information, 1944.
Medical student participating in a polio vaccine campaign in Mexico
A simplified diagram showing the process of immunization through the production of anti-bodies
If individuals make the decision to immunize based on the Private Marginal Benefit we see a quantity of Q1 at the price P1 while the socially optimal point is at quantity Q* and price P*. The distance between the private and marginal benefit lines is the cost of the marginal benefit to society.
Immunization A does not have a social marginal benefit large enough to shift Q1 to Q(e), instead it lands at Q*.
Immunization B has a social marginal benefit large enough to bring Q1 to Q(e), the quantity at which eradication occurs.
